The Northarctus is a extinct ancient primate, whose closet living relative is the Lemur , the Northarctus is also believed to be the mother of the modern primates.The Northarctus represented a huge leap in primate evolution as it has many features that are common in many types of primates today but are were not present in primates before it. The period in which this primate lived in is disputed however is believed by most scientists to be about 45-54 million years ago. This case study attempts to explain the reasons behind the extinction of this important primate. This report is about the Notharctus and will outline the following information:
Habitat
Behaviour Adaptation
Structural Adaptation
Physiological Adaptation
Extinction Pressure
General Information
Scientific Classification
Level
Classification
Kingdom
Animalia
Phylum
Chordata
Class
Mammalia
Order
Primates
Family
Notharctidae
Subfamily
Northarctinae
Genus
Northarctus
Habitat The Northarctus existed during the period that is known as the Eocene Epoch , the period lasted from 55 to 34 million years ago. It was the second epoch of the Palaeogene period of the Cenozoic era. The start of this epoch is marked by the emergence of the first of modern mammals, the Northarctus was one of those mammals. The end of this Epoch was marked at a major extinction event that is named the Grande Coupure which means the 'Great Break' in Continuity. Scientist predict that this Grande Coupure may be related to the impact of one or more large bolidea in Siberia in what is now know as Chesapeake Bay. The word Eocene means the 'dawn of modern mammalian fauna' in Greek.
File:Paleogene-EoceneGlobal.jpg
The is a paleogeographic reconstruction by scientists of the earth during the Eocene period which is about 50-36 million years ago
The Eocene period was a period of transformation, the continents were still drifting to their position and are nearer to each other than they are now. The first modern mammals that lived during this period also disappeared at the end of the period, the Northarctus was one of those mammals. The Northarctus lived in both Eurasia and North America, however a small group of Northarctus did make it to South America namely Madagascar where the modern day Lemur still lives. At the beginning of the Eocene period, high temperatures and warm oceans created a moist and balmy environment. This was an ideal environment for forests to spread all over the world from pole to pole with the exception of very deserts, this must have made an ideal environment for the Northarctus to live in. There was even fossil evidence that the subtropical and even tropical trees and plants grew as far north in the early Eocene period as Greenland and Alaska. Tropical rainforests also grew as far Europe and the Pacific Northwest. Towards the end of the period seasonal changes that brought cooler weather were occurring all over the earth. The cooling led to centre of many continents drying out and forests thinning out in many areas. Many tropical and subtropical trees were wiped out and replaced by deciduous trees that were better able to handle the large temperature changes. By the end of that period deciduous trees covered large parts of North American and Eurasia and the Arctic. Rainforests were only left in equatorial South America, Africa, India and Australia. Unlike the modern gorilla, the Northarctus had predators, carnivorous ungulates such as the Mesonyx. Carnivorous hoofed animals such as the Mesonyx were common around Europe and North America. The cooling weather meant that bigger animals were getting more common. This meant that there would be more and more predators of the Northarctus. Reptiles such as pythons and turtles were abundant at that time and remains of a snake that was as big as a small sized school bus have been found
Adaptations
Behaviour Adaptation 1
The Northarcus become a tree dweller as opposed to a land mammal. This adaptation probably happened because many of the predators that the Northarctus has were either reptiles or hoofed mammals which meant that that they would not be able to find it up in the trees because if the inability to climb up it. The less moist air that was present in the thick and moist air up in the trees would provide a good escape from the thick moist air of the forest floor that is often filled with predators.
The environmental pressure in this case is very obvious and clear, by being up in the trees, the Notharctus was able to live without fear of being pursued or having to escape from predators such as the Mesoynx and pythons. The Mesoynx was a hoofed predators that put fear into many of the animals that lived in the forest. The pythons were massive and were to big to be able to climb many of the trees that were really tall. Due to their small size, scientist think that the Notharctus even lived up in the trees which would mean that they would be able to sustain a life without fear of predators without ever having to leave the tree.
Behaviour Adaptation 2 The Notharctus started relying more on sight and vision rather than smells and sounds. This is probably because it started living up in the tress as opposed to staying on the ground like many of its ancestors did, this is due to the thick moist air in the forest floor that limits the visibility to a mere few metres which means that relying on vision would mean that would make them vulnerable to many different predators that lived on the forest floor and relied on other forms of senses such as sound and smell. The Notharctus was the first primate to rely more on the sense of sight and it paved the way for all of the modern day 'great apes that are far more advanced in terms of skills, brains and tool use than other mammals.
The forest floor as mentioned before was very dense and the air was moist and thick making visibility a mere few metres and if any animals relied on vision in that situation, they would go extinct really quick. However as the Notharctus starting living higher up in the trees visibility was improved and the having and relying on better vision and sight become a good thing compared to the past when relying solely on sight and nothing else would result in a recipe for disaster.
Structural Adaptation 1 The Notharctus had front facing eyes that would allow them to have stereoscopic vision, allowing them to see whats both in front and on the side. Most mammals and primates before it had side facing eyes and relied on a sense of the smell like modern day dogs to find food and sense danger. By having stereoscopic vision, the Notharctus had more than 100 degrees of vision and would be able to sense danger front the front more effectively and also see whats in front on them such as being able to see whats in their hand and therefore be able to use it newly evolved hands and feet better which will be explained in more detail in the next structural evolution paragraph.
By having front facing eyes, it allowed the Notharctus to focus on whats in front of them and still see whats on their side without having to tilt their head awkwardly to the side in order to see whats in front of them. The Notharctus was able to carry out tasks alot more effectively such as climbing, picking out fruits and eating them. These environmental pressures that were mentioned above would probably explain why the Notharctus would have evolved to have front facing eyes instead of side facing one which many of the primates before it had.
Structural Adaptation 2 The Notharctus had a flexible torso that was suited to leaping from tree to tree. The more flexible torso would allow the Notharctus to be more agile than its ancestors and therefore be able to climb the trees and jump from one branch to another due the flexible torso that gave them more agility than its ancestors that preceded it. The additional agility that was gained before of the more flexible torso was necessary for the Notharctus to survive in the environment that it survived in.
The Notharctus would need the added extra flexibility in the torso that its ancestors did not have because they were living up in there trees as opposed to their ancestors that led a life that was based on the ground and would require no where near the amount of jumping that that Notharctus would have needed during their existence. The flexible torso would also mean that they would be able to twist and turn mid flight, something that their ancestors would not require
Physiological Adaptation
The Notharctus switched from a primarily folivorous diet to a frugivorous diet. This probably happened because it lived in the trees unlike its ancestors that lived on the ground, on the ground there were fruits were a rarity while leafs were alot more common which would explain why its ancestor would lead a folivorous diet. However since the Notharctus lived up in the trees where fruits were abundant and it would also provide alot of the nutrients, vitatmins and energy that the leaves that their ancestors ate would not give them.
There was no real environmental pressure to change, however since there were better food available that what was available to their ancestors it made sense that they would change their diet as they had a better choice of food than their ancestors. The change in environment provided a bigger choice of food that offered better nutritional value than what was avalible before therefore it made sense to change.
This is artist's impression of how the gorilla might look like in their habitat during the Eocene Epoch based on descriptions by scientists
Extinction Pressure The end of the Eocene Epoch was marked by a single mass extinction. It is quite possible the that the Notharctus disappeared during the mass extinction, however it did leave 2 evolutions of it behind, the Lemur and a half evolved ape. This extinction was due to the huge amount of competition that the Notharctus faced from the many other animals that were suddenly appearing all over the place during toward the end of the Eocene Epoch. This was probably a very clear reason for this evolution as during the start and towards the middle of the Eocene Epoch Notharctus were spread all over the world while today the only place where the closest ancestors of the Notharctus, the Lemur is surviving is the Madagascar. However as some of the Notharctus did evolve in to a primate that is very similar to today's 'great apes' which proves that there are still some survivors of the mass extinction that were related to the Notharctus.
Introduction
The Northarctus is a extinct ancient primate, whose closet living relative is the Lemur , the Northarctus is also believed to be the mother of the modern primates.The Northarctus represented a huge leap in primate evolution as it has many features that are common in many types of primates today but are were not present in primates before it. The period in which this primate lived in is disputed however is believed by most scientists to be about 45-54 million years ago. This case study attempts to explain the reasons behind the extinction of this important primate.This report is about the Notharctus and will outline the following information:
General Information
Scientific ClassificationHabitat
The Northarctus existed during the period that is known as the Eocene Epoch , the period lasted from 55 to 34 million years ago. It was the second epoch of the Palaeogene period of the Cenozoic era. The start of this epoch is marked by the emergence of the first of modern mammals, the Northarctus was one of those mammals. The end of this Epoch was marked at a major extinction event that is named the Grande Coupure which means the 'Great Break' in Continuity. Scientist predict that this Grande Coupure may be related to the impact of one or more large bolidea in Siberia in what is now know as Chesapeake Bay. The word Eocene means the 'dawn of modern mammalian fauna' in Greek.
The is a paleogeographic reconstruction by scientists of the earth during the Eocene period which is about 50-36 million years ago
The Eocene period was a period of transformation, the continents were still drifting to their position and are nearer to each other than they are now. The first modern mammals that lived during this period also disappeared at the end of the period, the Northarctus was one of those mammals. The Northarctus lived in both Eurasia and North America, however a small group of Northarctus did make it to South America namely Madagascar where the modern day Lemur still lives.
At the beginning of the Eocene period, high temperatures and warm oceans created a moist and balmy environment. This was an ideal environment for forests to spread all over the world from pole to pole with the exception of very deserts, this must have made an ideal environment for the Northarctus to live in. There was even fossil evidence that the subtropical and even tropical trees and plants grew as far north in the early Eocene period as Greenland and Alaska. Tropical rainforests also grew as far Europe and the Pacific Northwest.
Towards the end of the period seasonal changes that brought cooler weather were occurring all over the earth. The cooling led to centre of many continents drying out and forests thinning out in many areas. Many tropical and subtropical trees were wiped out and replaced by deciduous trees that were better able to handle the large temperature changes. By the end of that period deciduous trees covered large parts of North American and Eurasia and the Arctic. Rainforests were only left in equatorial South America, Africa, India and Australia.
Unlike the modern gorilla, the Northarctus had predators, carnivorous ungulates such as the Mesonyx. Carnivorous hoofed animals such as the Mesonyx were common around Europe and North America. The cooling weather meant that bigger animals were getting more common. This meant that there would be more and more predators of the Northarctus. Reptiles such as pythons and turtles were abundant at that time and remains of a snake that was as big as a small sized school bus have been found
Adaptations
Behaviour Adaptation 1
The Northarcus become a tree dweller as opposed to a land mammal. This adaptation probably happened because many of the predators that the Northarctus has were either reptiles or hoofed mammals which meant that that they would not be able to find it up in the trees because if the inability to climb up it. The less moist air that was present in the thick and moist air up in the trees would provide a good escape from the thick moist air of the forest floor that is often filled with predators.
The environmental pressure in this case is very obvious and clear, by being up in the trees, the Notharctus was able to live without fear of being pursued or having to escape from predators such as the Mesoynx and pythons. The Mesoynx was a hoofed predators that put fear into many of the animals that lived in the forest. The pythons were massive and were to big to be able to climb many of the trees that were really tall. Due to their small size, scientist think that the Notharctus even lived up in the trees which would mean that they would be able to sustain a life without fear of predators without ever having to leave the tree.
Behaviour Adaptation 2
The Notharctus started relying more on sight and vision rather than smells and sounds. This is probably because it started living up in the tress as opposed to staying on the ground like many of its ancestors did, this is due to the thick moist air in the forest floor that limits the visibility to a mere few metres which means that relying on vision would mean that would make them vulnerable to many different predators that lived on the forest floor and relied on other forms of senses such as sound and smell. The Notharctus was the first primate to rely more on the sense of sight and it paved the way for all of the modern day 'great apes that are far more advanced in terms of skills, brains and tool use than other mammals.
The forest floor as mentioned before was very dense and the air was moist and thick making visibility a mere few metres and if any animals relied on vision in that situation, they would go extinct really quick. However as the Notharctus starting living higher up in the trees visibility was improved and the having and relying on better vision and sight become a good thing compared to the past when relying solely on sight and nothing else would result in a recipe for disaster.
Structural Adaptation 1
The Notharctus had front facing eyes that would allow them to have stereoscopic vision, allowing them to see whats both in front and on the side. Most mammals and primates before it had side facing eyes and relied on a sense of the smell like modern day dogs to find food and sense danger. By having stereoscopic vision, the Notharctus had more than 100 degrees of vision and would be able to sense danger front the front more effectively and also see whats in front on them such as being able to see whats in their hand and therefore be able to use it newly evolved hands and feet better which will be explained in more detail in the next structural evolution paragraph.
By having front facing eyes, it allowed the Notharctus to focus on whats in front of them and still see whats on their side without having to tilt their head awkwardly to the side in order to see whats in front of them. The Notharctus was able to carry out tasks alot more effectively such as climbing, picking out fruits and eating them. These environmental pressures that were mentioned above would probably explain why the Notharctus would have evolved to have front facing eyes instead of side facing one which many of the primates before it had.
Structural Adaptation 2
The Notharctus had a flexible torso that was suited to leaping from tree to tree. The more flexible torso would allow the Notharctus to be more agile than its ancestors and therefore be able to climb the trees and jump from one branch to another due the flexible torso that gave them more agility than its ancestors that preceded it. The additional agility that was gained before of the more flexible torso was necessary for the Notharctus to survive in the environment that it survived in.
The Notharctus would need the added extra flexibility in the torso that its ancestors did not have because they were living up in there trees as opposed to their ancestors that led a life that was based on the ground and would require no where near the amount of jumping that that Notharctus would have needed during their existence. The flexible torso would also mean that they would be able to twist and turn mid flight, something that their ancestors would not require
Physiological Adaptation
The Notharctus switched from a primarily folivorous diet to a frugivorous diet. This probably happened because it lived in the trees unlike its ancestors that lived on the ground, on the ground there were fruits were a rarity while leafs were alot more common which would explain why its ancestor would lead a folivorous diet. However since the Notharctus lived up in the trees where fruits were abundant and it would also provide alot of the nutrients, vitatmins and energy that the leaves that their ancestors ate would not give them.
There was no real environmental pressure to change, however since there were better food available that what was available to their ancestors it made sense that they would change their diet as they had a better choice of food than their ancestors. The change in environment provided a bigger choice of food that offered better nutritional value than what was avalible before therefore it made sense to change.
Extinction Pressure
The end of the Eocene Epoch was marked by a single mass extinction. It is quite possible the that the Notharctus disappeared during the mass extinction, however it did leave 2 evolutions of it behind, the Lemur and a half evolved ape. This extinction was due to the huge amount of competition that the Notharctus faced from the many other animals that were suddenly appearing all over the place during toward the end of the Eocene Epoch. This was probably a very clear reason for this evolution as during the start and towards the middle of the Eocene Epoch Notharctus were spread all over the world while today the only place where the closest ancestors of the Notharctus, the Lemur is surviving is the Madagascar. However as some of the Notharctus did evolve in to a primate that is very similar to today's 'great apes' which proves that there are still some survivors of the mass extinction that were related to the Notharctus.
Reference/Bibliography